1. Field of the Invention
The present invention relates to mobile communication terminals, and more particularly to a system and method for controlling the operation of a mobile communication terminal capable of providing a high-speed data rate service. The present invention further relates to a system and method for controlling the operation of a mobile communication terminal capable of providing a high-speed data rate service, while reducing the amount of battery power consumption and the amount of load on the terminal's hardware and software for various controls associated with two radio frequency receivers in the terminal.
2. Description of the Related Art
Recently, some mobile communication companies are preparing to implement a high-speed data rate (HDR) service which can improve the quality of a very high speed wireless Internet service while being connected with code division multiple access (CDMA) 2000-1x. HDR service supports no separate voice service, but instead, has an excellent data transfer capability which surpasses that of existing very high speed wired Internet services.
HDR service also provides for the commercial availability of a CDMA2000-1x evolution data only (EVDO) service, which is called a very high speed wireless data communication service based on a 2-generation network. The EVDO service is considered to be a synchronous international mobile telecommunication (IMT)-2000 (3rd generation: 3G) technique, because it has a transfer rate which is ten times or more higher than that of a CDMA 2000-1x (IS95C) service, called a 2.5-generation service. The HDR service is also appropriate for high-speed wireless Internet service in that it provides a maximum forward data rate of 2.4 Mbps, and a maximum reverse data rate of 153.6 Kbps, by assigning a data dedicated channel. Furthermore, the HDR service may be used to enhance a data transfer capability in an existing CDMA 2000-1x (IS95C) network or in an independent data network. In the existing CDMA network, some voice channels are converted into data channels. However, the HDR service employs the combination of time division multiplexing (TDM) and CDMA to allow several users to share each channel with one another. Also, the HDR service does not have a time band fixed as in time division multiple access (TDMA), but rather uses the time band only as needed. Data rates of the HDR service for the optimum connection with Internet protocol (IP) packets over the Internet will be different according to the respective distances from mobile communication terminals to a base station.
As a result, a mobile communication terminal supporting the EVDO service can provide services and transmit and receive moving images in real time, at a data rate of 2 Mbps or more, thus surpassing that of the very high speed wired Internet service. This type of mobile communication terminal uses a space diversity technology employing two antennas and has two radio frequency receivers, so as to minimize loss of received information resulting from fading.
However, such a mobile communication terminal has a disadvantage in that more battery power is consumed since two antennas and two radio frequency receivers are used together. Furthermore, a larger load is applied to the terminal's hardware and software for various controls associated with the two radio frequency receivers.